Concern over air quality has triggered much interest and many developments in the area of indoor air quality improvement and/or control. Such developments have resulted in the production of various types of air processing devices including air filtration apparatus. Air filtration apparatus are often differentiated according to air filtering capabilities and generally include air filtration devices designed to be integrated within a heating, ventilation, and air conditioning (HVAC) system and local or unitary air filtration devices. Air filtration devices configured to be integrated with HVAC systems (i.e., integrated air filtration devices) are typically capable of filtering large amounts of ambient air such as, for example, an amount of ambient air that fills a warehouse, an office building, an apartment building, a house, an entertainment hall, etc. In contrast, local or unitary air filtration devices are typically configured to filter an amount of ambient air associated with a local area such as, for example, an office, a bedroom, a bathroom, etc.
Integrated air filtration devices are typically large, bulky, and aesthetically unpleasing devices that are usually installed, for example, in a ceiling plenum, in a mechanical room, on a building roof top or otherwise outside of a building or structure, etc. By installing such integrated area air filtration devices in plenum spaces, on the outside of buildings, etc., integrated air filtration devices do not occupy valuable space (e.g., living space, work space, etc.) within the buildings and remain hidden from the view of building occupants.
In contrast, local or unitary air filtration devices are typically physically smaller than integrated air filtration devices and, thus, may be readily movable or portable from one space to another. Local or unitary air filtration devices are typically employed by individuals to improve the air quality within an immediate or local area such as, for example, an office, a family room, a bathroom, etc. The smaller size of these local or unitary air filtration devices enables one or more of these devices to be placed in various locations throughout a space or area (e.g., a room) within which ambient air is to be filtered. In addition, the local or unitary air filtration devices are typically designed to be placed in locations that are within the view of occupants of the locations. For example, the physical structures (e.g., enclosure or housing components) of these air filtration devices may be designed to be aesthetically pleasing and/or to be as unobtrusive as possible in view of other objects (e.g., firnishings, decor, etc.),that are typically present in the occupied spaces or areas.
Each type of air filtration device is typically configured to target specific filtering needs or requirements. For example, HVAC system integrated air filtration devices are configured to filter large amounts of ambient air over extended periods of time. In many cases, a considerable amount of time is required to filter all of the air within an entire building or structure. This is often acceptable for structures requiring minimal air filtration or that experience a relatively low rate of air quality degradation. In buildings or structures within which the rate of air quality degradation is relatively low, an HVAC system integrated air filtration device may operate only occasionally to maintain an acceptable air quality rating. However, in other buildings or structures such as, for example, bars, casinos, night clubs, etc., within which the rate of air quality degradation is relatively high, the integrated air filtration device may work continuously to maintain an acceptable air quality. In some cases, structures having higher rates of air quality degradation require larger HVAC system integrated air filtration devices. Many buildings or structures have multiple areas or spaces, each of which has a different air quality degradation rate and/or characteristic. Such areas or spaces may include high traffic (e.g., high occupancy density) areas smoking areas, non-smoking areas, etc. However, HVAC system integrated air filtration devices are typically configured to filter all or many areas within a structure at the same time and in the same manner (e.g., evenly). As a result, such HVAC system integrated air filtration devices are unable to filter the air in some areas more than other areas.
An alternative or additional approach to addressing the needs of spaces having larger rates of air quality degradation and/or a plurality of areas having different air quality degradation rates involves the use of a plurality of local or unitary air filtration devices distributed throughout the spaces and/or areas. In this manner, the plurality of air filtration devices may operate to filter the air in a relatively large area or an entire building by cooperating to filter the ambient air in multiple local areas. For example, an air filtration device in one area or space may be operated at a different air filtration rate than an air filtration device located in another area or space.
Installing or locating a local or unitary air filtration device in a space or area consumes a certain amount of space (e.g., floor space). When installing a single local air filtration device within an office or a household room, the amount of space occupied by that air filtration device may be insignificant. However, when installing a plurality of air filtration devices throughout a building or a structure to filter large amounts of air as described above, the total space occupied by those air filtration devices may be a significant amount of space that could otherwise be used as functional space within the building or structure.
One solution to reduce the amount of space required by a plurality of local air filtration devices located within a space or spaces involves reducing the required number of air filtration devices by, for example, increasing the air filtering capacity of each local air filtration device. In this manner, fewer air filtration devices are needed to achieve a desired air quality. However, this approach may lead to larger, noisier, and more obtrusive air filtration devices that are not appealing to purchasers of the air filtration devices or to patrons of a business (e.g., a mall, a casino, a bar, etc.) operating in the area(s) within which the larger local air filtration devices are located.